BACKGROUND: One in ten Americans age 65 and older are currently diagnosed with Alzheimer?s disease. Although Alzheimer?s disease was identified more than 100 years ago, racial disparities in the disease continue to persist. Research has consistently indicated that among all racial groups, African Americans have the highest Alzheimer?s disease risk, which is nearly twice as high compared to White older adults. Despite the wide scientific evidence for this disparity, the reasons for these racial differences in Alzheimer?s disease risk remain unclear. Prior research indicates that lifestyle behaviors are associated with Alzheimer?s disease risk. Further, African Americans have been noted to have a higher prevalence of poor lifestyle behaviors associated with Alzheimer?s disease, such as physical inactivity and cigarette smoking. While numerous studies have explored how lifestyle behaviors are associated with Alzheimer?s disease risk, there has been no research that has examined whether lifestyle behaviors contribute to racial differences in Alzheimer?s disease. This proposed study explores engagement in three particular lifestyle behaviors: physical activity, cigarette smoking, and social contacts. With this in consideration, the central objective of this study is to investigate the influence of lifestyle behaviors on the differential risk for Alzheimer?s disease/dementia between White and African American older adults. To better understand this relationship, this study has three aims: 1) To determine the influence of lifestyle behaviors on Alzheimer?s disease/dementia risk among older adults, 2) To determine how lifestyle behaviors influence racial differences in Alzheimer?s disease/dementia risk between White and African American older adults, and 3) To determine how race moderates the relationship between lifestyle behaviors and Alzheimer?s disease/dementia risk among older adults. METHODS: This study will use secondary data from the National Health and Aging Trends Study (NHATS), a longitudinal panel study that surveys a nationally representative sample of more than 12,000 older adults age 65 and older within the United States. All available NHATS data from 2011 to 2016 will be used for this study. The dependent variable is age of Alzheimer?s disease/dementia diagnosis. The primary independent variables are individual and cumulative engagement in physical activity, smoking, and social contacts. Each aim will be analyzed with Cox proportional hazard models, while controlling for sociodemographics and health. IMPLICATIONS: Findings from this study will offer major implications for public health by providing insight into how certain lifestyle behaviors can influence the onset of Alzheimer?s disease. Further, findings from this study may reveal whether lifestyle behaviors contribute to racial differences in Alzheimer?s disease, which may be crucial in addressing racial disparities by indicating which lifestyle behaviors may be especially protective in reducing Alzheimer?s disease risk among African Americans.